This invention relates generally, to valve operating devices and more particularly, to an improved valve actuating apparatus adapted to be remotely controlled.
The transmission of fluids through pipelines is most often regulated by the use of suitable displaceable valve members. In the majority of situations, the valve is operated by manually displacing the valve stem such as by turning a wheel affixed thereto. However, in the case of potentially dangerous installations, it is desirable to minimize risks to workers involved in the operation of valves and this may be achieved by allowing for indirect or remote actuation of the valves. In this manner, should a break occur in a valve or associated pipeline, the operator would not be injured or killed by either flying structural debris or escaping contents of the pipeline.
The use of a remotely controlled valve operator satisifes a primary concern, particularly in certain pipelines. This concern involves the safety of personnel in the vicinity of a valve, not the least of which is the actual individual assigned to open or close a valve. There have been recorded many instances whereby a worker has been at least maimed while operating a valve. Such injuries have resulted from numerous causes including faulty valve housings, bonnet fasteners or seals or even failure of the threaded juncture between the valve housing and associated pipe strings. These failures of course may be further induced by a sudden excessive pressure within the pipeline system although it will be appreciated that a mechanical flaw in the pipe or valve structure can lead to a structural failure at practically any pressure within the system. Although well head valves as used in the natural oil and gas industry quite obviously may employ and benefit from use of the present invention, it will be appreciated that valved pipelines as used in other industries, such as chemical or steam pipelines, may utilize a remote valve operator.
Several devices have been suggested in the past for remotely operating a pipeline valve. U.S. Pat. No. 3,387,748 issued June 11, 1968 to Brenchley discloses an electric motor attached to a pipeline valve and actuated by a timing device remotely joined to the motor by wiring. Another example will be found in U.S. Pat. No. 3,972,506 wherein, a motor stationed adjacent a valve and joined thereto by a flexible shaft, is controlled from a remotely disposed location. In both of these prior assemblies, special provision is required for the support of the motor unit while modification of the valve stem is also necessary, to accommodate the motor output.